Memory and luminescence properties of Si nanocrystals fabricated by ion beam mixing

Ion irradiation induced interface mixing was used to generate silicon nanocrystals at the SiO2-Si interface of metal-oxide-semiconductor (MOS) structures aiming at electronic memory applications, photoluminescence as well as electroluminescence. No particular processing issues have been encountered during integration of this technique in standard submicronic C-MOS technology. The memory properties of the fabricated structures as a function of the Si+-irradiation dose as well as annealing temperature and time have been examined through electrical measurements of capacitors and transistors. Low-voltage operating devices that can endure more than 10^6 programming/erasing cycles have been successfully achieved. While excellent device uniformity and reproducibility have been observed over 6-inch wafers, more research is still required to improve charge retention. The photoluminescence of the ion irradiated MOS structure gives a profile in the red region which is typical for Si nanocrystals. Preliminary results about the electroluminescence caused by an applied ac voltage will be reported too.